When less is more: feedback, priming, and the pseudoword superiority effect

Abstract

The present study combined masked priming with electrophysiological recordings to investigate orthographic priming effects with nonword targets. Targets were pronounceable nonwords (e.g., STRENG) or consonant strings (e.g., STRBNG), that both differed from a real word by a single letter substitution (STRONG). Targets were preceded by related primes that could be the same as the target (e.g., streng-STRENG, strbng-STRBNG) or the real word neighbor of the target (e.g., strong-STRENG, strong-STRBNG). Independently of priming, pronounceable nonwords were associated with larger negativities than consonant strings, starting at 290ms post-target onset. Overall, priming effects were stronger and longer-lasting with pronounceable nonwords than consonant strings. However, consonant string targets showed an early effect of word neighbor priming in the absence of an effect of repetition priming, whereas pronounceable nonwords showed both repetition and word neighbor priming effects in the same time window. This pattern of priming effects is taken as evidence for feedback from whole-word orthographic representations activated by the prime stimulus that influences bottom-up processing of prelexical representations during target processing.

Figure 1

Sequence of events on a typical trial with example stimuli for the word neighbor prime and consonant string target condition.

Figure 2

Electrode montage and four analysis columns used for ANOVAs.

Figure 3

Left: ERPs time locked to target onset in two conditions (black line: full repetition; red line: unrelated prime) over 9 electrode sites, for pronounceable nonwords (above) and for consonant strings (below). Right: Voltage maps centered on the three epochs used in the statistical analyses. The maps represent voltage differences at each electrode site calculated by subtracting the voltage values in the related prime condition from the voltage values in the unrelated prime condition.

Figure 4

Left: ERPs time locked to target onset in two conditions (black line: word neighbor prime; red line: unrelated word prime) over 9 electrode sites, for pronounceable nonwords (above) and for consonant strings (below). Right: Voltage maps centered on the three epochs used in the statistical analyses. The maps represent voltage differences at each electrode site calculated by subtracting the voltage values in the related prime condition from the voltage values in the unrelated prime condition.

Figure 5

Main effect of Type-of-Target at O1 and Cz electrode sites, and voltage maps representing the voltage differences (pronounceable nonwords vs. consonant strings) at all electrode sites.

Figure 6

Voltage maps subtracting the voltage values in the related prime condition from the voltage values in the corresponding unrelated prime condition for pronounceable nonword targets in seven successive 50 ms time-windows starting from 150 ms post-target onset.

Figure 7

Voltage maps subtracting the voltage values in the related prime condition from the voltage values in the corresponding unrelated prime condition for consonant string targets in seven successive 50 ms time-windows starting from 150 ms post-target onset.